Northern Blue (Plebejus idas)

Description: A small, deep blue butterfly. Males are bright blue above, with narrow dark margins. Females are dark brown above, often with a dark marginal spots on the hindwing and orange submarginal bands on both wings. The underside is pale grey with black spots. The marginal spots of the hindwing have metallic blue centers and black and orange caps.
Wingspan: 17 to 28 mm.

Maritime Distribution: In coastal bogs and headlands throughout the Maritimes. For Atlas results click here.

Provincial Ranks: NB: S3. NS: S5. PEI: S2.

Flight Period: Late June to early August.

Host Plant: The subspecies that occurs in the Maritimes, empetri, feeds on Black Crowberry (Empetrum nigrum).

Subspecies: So far only subspecies empetri has been found in the Maritimes although it is possible that subspecies scudderi may enter northern New Brunswick in inland areas.

Notes: The Crowberry Blue is locally common in bogs and on coastal headlands throughout the Maritimes where its host plant, Black Crowberry, grows. It often flies in the fog and rain in coastal areas where sunny weather can be infrequent. It frequently flies alongside the Bog Copper, especially in bogs and barrens along the Atlantic and Fundy coasts.